Aside from the fact that even just the driving around ACT even under vacuum would be through the roof without some sort of aftercooler to control them, the current lower manifold offerings (stock or GT40) wouldn't even come close to being able to move the volume of airflow a 2.8L would support. I doubt you’d even come close to getting the blower into its efficiency range without having it all stack up on the intake side.....even with the lower manifold ported.

I suspect it would be great for bragging about the fact that you've got a 2.8L under the hood, but little else.

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Oh, I understand, even a ported GT40 lower is going to choke a healthy 347 NA. If you were going to go with a custom setup like that, seems to me a custom sheet metal lower would be in order.

Mod Dude

Are there efficiency charts for twin-screw blowers? I'd love to see how one compares with a turbo/centri compressor.

Also, if a ported GT40 lower is good enough for 320 rwhp n/a, why would it choke a 2.8L KB? How much power do those motors make at 15psi, or roughly 2 bar on 4.6L motors? I mean, that 320 rwhp windsor should be pump over 600-ish rwhp at that pressure.

Are there efficiency charts for twin-screw blowers? I'd love to see how one compares with a turbo/centri compressor.

Also, if a ported GT40 lower is good enough for 320 rwhp n/a, why would it choke a 2.8L KB? How much power do those motors make at 15psi, or roughly 2 bar on 4.6L motors? I mean, that 320 rwhp windsor should be pump over 600-ish rwhp at that pressure.

Chris

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im not even sure it would be possible to run a 2.8 on the car so i doubt it would matter

if your just going for a occasional track car with daily duties turbo is the way to go. when i had my 91 eagle talon TSi i had full spool at 2800rpm you just have to make sure the turbo is sized right for the engine. call hellion or hp they will hook you up. lets face it when you can get 330 ft/lbs of toruqe out of a 2 litre 4 banger you've done something right. i seen that car run 9.95 at 143 and drive 25 miles to the track. and with a 2-way boost controller its back to docile at the flick of a switch.

if your just going for a occasional track car with daily duties turbo is the way to go. when i had my 91 eagle talon TSi i had full spool at 2800rpm you just have to make sure the turbo is sized right for the engine. call hellion or hp they will hook you up. lets face it when you can get 330 ft/lbs of toruqe out of a 2 litre 4 banger you've done something right. i seen that car run 9.95 at 143 and drive 25 miles to the track. and with a 2-way boost controller its back to docile at the flick of a switch.

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turbo isnt gonna happen, might not get tracked much but will see street time even less, this is not my DD not even close, i have a truck for that

Mod Dude

if your just going for a occasional track car with daily duties turbo is the way to go. when i had my 91 eagle talon TSi i had full spool at 2800rpm you just have to make sure the turbo is sized right for the engine. call hellion or hp they will hook you up. lets face it when you can get 330 ft/lbs of toruqe out of a 2 litre 4 banger you've done something right. i seen that car run 9.95 at 143 and drive 25 miles to the track. and with a 2-way boost controller its back to docile at the flick of a switch.

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But a 750 rwhp turbo is not going to spool that low on a 331 cube motor. That's at least a 70mm turbo. Sizing a turbo is a give and take game. If you want to take more power, you have to give up spool time.

On a side note, you saw a car with 330 ft-lbs run 9.95@143? How much did said car weigh? These numbers do not add up unless it was making that torque at 10-12,000 rpm or the car weighs around 1500 lbs.

On a side note, you saw a car with 330 ft-lbs run 9.95@143? How much did said car weigh? These numbers do not add up unless it was making that torque at 10-12,000 rpm or the car weighs around 1500 lbs.

Super Mod

custom sheet medal intake with a 03 cobra or lightning intercooler would be a route id be looking into.

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I hope you've got a 10" cowl hood to go along with it. The Cobra/Lightning intercooler is one thick mo-fo. Remember the engine valley between the heads is no where near as deep on the OHV engines as it is on the OHC ones. Hence the reason many PD blower kids now actually invert their blower on the 2V and 3V SOCH engines. There's just so much unused real estate under there, they'd be a fool not to take advantage.

I hope you've got a 10" cowl hood to go along with it. The Cobra/Lightning intercooler is one thick mo-fo. Remember the engine valley between the heads is no where near as deep on the OHV engines as it is on the OHC ones. Hence the reason many PD blower kids now actually invert their blower on the 2V and 3V SOCH engines. There's just so much unused real estate under there, they'd be a fool not to take advantage.

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i know exactly how big it is... i worked for amazon racing for a VERY long time ive pulled a few blowers out. but if you look at the 2.8H its only about 6 inches tall and about another 6-7 for the intercooler. a 4 inch cowl should be enough to clear it id think. should be any taller then say a lightning motor which i think needs a 6" cowl to clear

i know exactly how big it is... i worked for amazon racing for a VERY long time ive pulled a few blowers out. but if you look at the 2.8H its only about 6 inches tall and about another 6-7 for the intercooler. a 4 inch cowl should be enough to clear it id think. should be any taller then say a lightning motor which i think needs a 6" cowl to clear

Super Mod

i know exactly how big it is... i worked for amazon racing for a VERY long time ive pulled a few blowers out. but if you look at the 2.8H its only about 6 inches tall and about another 6-7 for the intercooler. a 4 inch cowl should be enough to clear it id think. should be any taller then say a lightning motor which i think needs a 6" cowl to clear

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Don’t take this the wrong way, but it really doesn’t matter where you worked to be quite honest, You still seem to have missed the point I was trying to make. You literally don't have the real estate in the oil galley on an OHV 302 to work with that you do an OHC engine. Yes, it requires approx a 7” cowl hood in a Fox body (at least that what was needed with MM&FF’s Project Frightning a couple years back) with a complete lightning engine, but we’re talking lightning blower and intercooler with a custom manifold on an OHV engine….not an OHC. Its gong to be considerably more than just 12 or 13” of Blower + Brick in over overall height…especially when you consider having to factor in the actual manifold itself into that equation.

Take a good look at Frightning and try to visualize what it would need to look like with the need for even more hood clearance?!?

…and this was bolted to its original 5.4L SOHC engine, with their original use of a 4” cowl hood

The OHV engine doesn’t have a deep intake galley to work with like the OHC does. You’d have to increase the intake height and therefore the brick and blower height considerably just to elevate the intercooler brick high enough in the galley to keep it from sitting on top of lifter bosses. On top of than, you’ve got 16-pushrods in close proximity also in the way, which requires even more elevation still. You’d actually be further ahead with a 351W as a custom set up than you would a 302W, since you’ve got an extra 1-2” of width to work with.

Here’s another example of a 6-71 on a 351W intake.

Even if you disregard the top feed carb inlet, the physical size of the 671 isn’t more than about 2-3” taller than the 2.8L H. Take into account that even with the difference in height, the picture blow has zero provision for another 7” of intercooler brick and increased manifold depth and there’s no way you’re getting that thing under a 4” cowl hood. Not in this lifetime!

No, I stand by my original statement of at least 10” of cowl hood needed to make it work.

lightning intake is kinda on the overly large side... its got a inch or 2 gap between the blower and the intercooler then its got that plentum on top of the blower the kb enters in the back... im not saying its going to be an easy task but i think it can be done. just need to be creative